Study On The Performance Of Cement Stabilized Macadam Containing Recycled Aggregate Based On Vibration Mixing Technology

In order to meet the large demand for cement stabilized macadam base in the development of highway transportation industry and solve the problem of construction waste disposal caused by social construction,this paper replaces part or all of the recycled aggregate prepared by sorting,crushing and screening of construction waste with natural aggregate to prepare cement stabilized macadam materials.At the same time,in order to improve the performance of cement stabilized macadam containing recycled aggregate,this paper studies the influence of vibration mixing technology on the strength and frost resistance of cement stabilized macadam containing recycled aggregate from the mixing process of preparing cement stabilized macadam,so as to expand the application range of cement stabilized macadam containing recycled aggregate.Firstly,this paper studies the difference between the performance of recycled aggregate and natural aggregate through raw material test,and determines the mixture gradation and compaction test method suitable for cement stabilized macadam containing recycled aggregate according to the test results of raw materials.Secondly,the vibration strength of the vibration mixer used in this test was calibrated,and on this basis,the test scheme was determined.The vibration mixing and ordinary forced mixing cement stabilized macadam with the same recycled aggregate substitution rate were compared.The test content includes strength performance and frost resistance.The performance of cement stabilized macadam containing recycled aggregate and the influence of vibration mixing technology on the performance of cement stabilized macadam containing recycled aggregate were analyzed by combining theoretical analysis with experimental research.The test results show that the recycled aggregate has lower density and strength than the natural aggregate,while the water absorption,crushing value and needle-like content are large.The median value of the skeleton dense gradation range is selected for the gradation of the mixture,and the vibration compaction is selected for the compaction test method.It can be concluded from the compaction test results that as the replacement rate of recycled aggregate increases from 0% to 100%,the maximum dry density decreases by about 23%,and the optimum water content increases by about 171%.With the increase of recycled aggregate replacement rate,the strength and frost resistance of cement stabilized macadam decrease,but with the increase of curing age and cement content,the strength and frost resistance of cement stabilized macadam are improved.Compared with ordinary forced mixing,the overall performance of cement stabilized macadam containing recycled aggregate prepared by vibration mixing technology is improved.The increase percentage depends on the cement content and vibration strength.The larger the cement content,the smaller the percentage of strength improvement by vibration mixing.Under the same cement content,with the increase of vibration strength,the strength and frost resistance of cement stabilized macadam containing recycled aggregate increase first and then remain stable.Considering the life and reliability of the mixer,it is recommended to use vibration strength VM2(vibration acceleration is 2.56 g).Under the same cement content and curing age,compared with the ordinary mixing technology,the coefficient of variation of the compressive strength and splitting strength of the cement stabilized gravel using the vibration mixing technology is mostly small,indicating that the vibration mixing technology can significantly improve the uniformity of the cement stabilized gravel mixture.